Knowledge-Based Genetic Algorithm Approach To Quantization Table Generation For The Jpeg Baseline Algorithm,
2016
TÜBİTAK
Knowledge-Based Genetic Algorithm Approach To Quantization Table Generation For The Jpeg Baseline Algorithm, Vinoth Kumar Balasubramanian, Karpagam Manavalan
Turkish Journal of Electrical Engineering and Computer Sciences
JPEG has played an important role in the image compression field for the past two decades. Quantization tables in the JPEG scheme is a key factor that is responsible for compression/quality trade-off. Finding the optimal quantization table is an open research problem. Studies recommend the genetic algorithm to generate the optimal solution. Recent reports revealed optimal quantization table generation based on a classical genetic algorithm (CGA). Although the CGA produces better results, it shows inefficiency in terms of convergence speed and productivity of feasible solutions. This paper proposes a knowledge-based genetic algorithm (KBGA), which combines the image characteristics and knowledge …
High Dynamic Performance Of A Bldc Motor With A Front End Converter Using An Fpga Based Controller For Electric Vehicle Application, Praveen Yadav, Rajesh Poola, Khaja Najumudeen
Turkish Journal of Electrical Engineering and Computer Sciences
This paper focus on a novel operation of a brushless dc (BLDC) motor fed by a proportional integral (PI) controlled buck--boost converter supplemented with a battery to provide the required power to drive the BLDC motor. The operational characteristics of the proposed BLDC motor drive system for constant as well as step changes in dc link voltage of a front end converter controlled by a Xilinx System Generator (XSG) based PI controller for two quadrant operations are derived. Thus a field programmable gate array (FPGA) based PI controller manages the energy flow through the battery and the front end converter. …
Scalable Sentiment Analytics,
2016
TÜBİTAK
Scalable Sentiment Analytics, Aslan Baki̇rov, Kevser Nur Çoğalmiş, Ahmet Bulut
Turkish Journal of Electrical Engineering and Computer Sciences
Spark has become a widely popular analytics framework that provides an implementation of the equally popular MapReduce programming model. Hadoop is an Apache foundation framework that can be used for processing large datasets on a cluster of computers using the MapReduce programming model. Mahout is an Apache foundation project developed for building scalable machine learning libraries, which includes built-in machine learning classifiers. In this paper, we show how to build a simple text classifier on Spark, Apache Hadoop, and Apache Mahout for extracting out sentiments from a text collection containing millions of text documents. Using a collection of 7 million …
Study Of The Icing Growth Characteristic And Its Influencing Factors For Different Types Of Insulators,
2016
TÜBİTAK
Study Of The Icing Growth Characteristic And Its Influencing Factors For Different Types Of Insulators, Zhijing Zhang, Dongdong Zhang, Haizhou Huang, Xingliang Jiang, David Wenzhong Gao
Turkish Journal of Electrical Engineering and Computer Sciences
Icing poses a serious threat to power transmission in many countries. Various studies on the icing mechanism and icing growth process of transmission lines have been carried out all over the world, whereas there are few reports about the icing growth mechanism and its influencing factors on insulators to date. In this paper, artificial tests of insulator icing were carried out; the influences of temperature, median volumetric diameter (MVD), and wind velocity on the icing accretion process, ice shape, and ice type on the surface of insulators were analyzed systematically; and the icing growth performance of different types of insulators …
Scale Invariant And Fixed-Length Feature Extraction By Integrating Discrete Cosine Transform And Autoregressive Signal Modeling For Palmprint Identification, Burhan Ergen
Turkish Journal of Electrical Engineering and Computer Sciences
Recently, the need for automatic identification has caused researchers to focus on biometric identification methods. Palmprint-based biometric identification has several advantages such as user friendliness, low-cost capturing devices, and robustness. In this paper, a method that integrates the discrete cosine transform (DCT) and an autoregressive (AR) signal modeling is proposed for biometric identification. The method provides scale invariance and produces a fixed-length feature vector. In particular, the Burg algorithm is used for the determination of the AR parameters used as a feature vector. Experimental results demonstrate that a small number of the AR parameters that are modeling the DCT coefficients …
Reinforcement Learning-Based Mobile Robot Navigation,
2016
TÜBİTAK
Reinforcement Learning-Based Mobile Robot Navigation, Ni̇hal Altuntaş, Erkan İmal, Nahi̇t Emanet, Ceyda Nur Öztürk
Turkish Journal of Electrical Engineering and Computer Sciences
In recent decades, reinforcement learning (RL) has been widely used in different research fields ranging from psychology to computer science. The unfeasibility of sampling all possibilities for continuous-state problems and the absence of an explicit teacher make RL algorithms preferable for supervised learning in the machine learning area, as the optimal control problem has become a popular subject of research. In this study, a system is proposed to solve mobile robot navigation by opting for the most popular two RL algorithms, Sarsa($\lambda )$ and Q($\lambda )$. The proposed system, developed in MATLAB, uses state and action sets, defined in a …
Bone Age Determination In Young Children (Newborn To 6 Years Old) Using Support Vector Machines,
2016
TÜBİTAK
Bone Age Determination In Young Children (Newborn To 6 Years Old) Using Support Vector Machines, Gür Emre Güraksin, Harun Uğuz, Ömer Kaan Baykan
Turkish Journal of Electrical Engineering and Computer Sciences
Bone age is assessed through a radiological analysis of the left-hand wrist and is then compared to chronological age. A conflict between these two values indicates an abnormality in the development process of the skeleton. This study, conducted on children aged between 0 and 6 years, proposes a computer-based diagnostic system to eliminate the disadvantages of the methods used in bone age determination. For this purpose, primarily an image processing procedure was applied to the X-ray images of the left-hand wrist of children from different ethnic groups aged between 0 and 6 years. A total of 9 features, corresponding to …
An Intelligent Design Optimization Of A Permanent Magnet Synchronous Motor By Artificial Bee Colony Algorithm,
2016
TÜBİTAK
An Intelligent Design Optimization Of A Permanent Magnet Synchronous Motor By Artificial Bee Colony Algorithm, Mümtaz Mutluer, Osman Bi̇lgi̇n
Turkish Journal of Electrical Engineering and Computer Sciences
The artificial bee colony algorithm is one of the latest stochastic methods based on swarm intelligence. The algorithm simulates the foraging behavior of honeybees. The structure of the algorithm is quite simple and its coding is very easy. This paper proposes a design optimization based on geometrical variables to obtain a highly efficient surface-mounted permanent magnet synchronous motor with concentrated winding by use of the artificial bee colony algorithm. Input parameters for the algorithm are the geometrical variables of the motor. This approach is more advantageous than finite element analysis requiring a long period of time. Results of the artificial …
Multiple Perspectives On The Hardware Implementations Of Biological Neuron Models And Programmable Design Aspects,
2016
TÜBİTAK
Multiple Perspectives On The Hardware Implementations Of Biological Neuron Models And Programmable Design Aspects, Ni̇met Korkmaz, İsmai̇l Öztürk, Recai̇ Kiliç
Turkish Journal of Electrical Engineering and Computer Sciences
A few individual design examples of programmable device-based biological neuron model implementations are available in the literature, but there is no comprehensive study that examines analog and digital programmable design examples of frequently studied biological neuron model implementations. The aim of this paper is to present a comparative study about programmable and reconfigurable implementations of the FitzHugh--Nagumo, Izhikevich, and Hindmarsh--Rose neuron models. Since field programmable analog array (FPAA) and field programmable gate array (FPGA) devices offer several advantages such as flexible design possibilities, reduction of the complexity of design, real-time modification, and software control for programmable and reconfigurable implementations of …
Optimal Power Flow By Considering System Security Cost And Small Signal Stability Constraints,
2016
TÜBİTAK
Optimal Power Flow By Considering System Security Cost And Small Signal Stability Constraints, Mohammad Sarvi, Mohammad Reza Salimian
Turkish Journal of Electrical Engineering and Computer Sciences
The main objective of optimal power flow is to find the proper operating point for the power system. In this paper, the optimal power flow by considering system security cost (OPFSC) and the small signal stability constraint is presented. For this purpose, the total profit of the system by considering the system constraints is optimized. The total profit of the system is equal to the combination of profit from the active power consumption, active power generation cost, and system security cost. System security cost includes the cost of load shedding, which is computed for all contingencies that may occur in …
Computation Of The Scattered Fields From An Arbitrary Discontinuity On A Perfectly Conducting Ground Plane By A Decomposition Method, Ahmet Kizilay, Uğur Saynak
Turkish Journal of Electrical Engineering and Computer Sciences
A novel procedure for solving plane wave incident on arbitrary bump or cavity geometries on a perfectly conducting ground plane is introduced. The method is presented with examples for transverse-magnetic polarization compared to various other solution methods. The proposed method can be easily generalized to other similar problems.
A New Fuzzy Membership Assignment And Model Selection Approach Based On Dynamic Class Centers For Fuzzy Svm Family Using The Firefly Algorithm, Omid Naghash Almasi, Modjtaba Rouhani
Turkish Journal of Electrical Engineering and Computer Sciences
The support vector machine (SVM) is a powerful tool for classification problems. Unfortunately, the training phase of the SVM is highly sensitive to noises in the training set. Noises are inevitable in real-world applications. To overcome this problem, the SVM was extended to a fuzzy SVM by assigning an appropriate fuzzy membership to each data point. However, suitable choice of fuzzy memberships and an accurate model selection raise fundamental issues. In this paper, we propose a new method based on optimization methods to simultaneously generate appropriate fuzzy membership and solve the model selection problem for the SVM family in linear/nonlinear …
Penalty Factor-Based Optimization Algorithm For Distributed Generation Sizing In Distribution Network,
2016
TÜBİTAK
Penalty Factor-Based Optimization Algorithm For Distributed Generation Sizing In Distribution Network, Jasrul Jamani Jamian, Mohd Nabil Bin Muhtazaruddin, Muhammad Ariff Baharuddin
Turkish Journal of Electrical Engineering and Computer Sciences
The installation of distributed generation (DG) can be used to minimize the total power loss in the distribution network. Besides that, other power system performances such as voltage profile, stability index, and total harmonic distortion can also be improved via DG. Although many works on DG have been done, most researchers have assumed that the distribution line is in an ideal condition (unlimited capacity limit). On the contrary, all practical lines should have their own capacity limit. Therefore, the main contribution of this paper is to determine the optimal DG output that can fulfill the maximum allowable line capacity limit …
System Identification By Using Migrating Birds Optimization Algorithm: A Comparative Performance Analysis,
2016
TÜBİTAK
System Identification By Using Migrating Birds Optimization Algorithm: A Comparative Performance Analysis, Hasan Makas, Nejat Yumuşak
Turkish Journal of Electrical Engineering and Computer Sciences
System identification is an important process to investigate and understand the behavior of an unknown system. It aims to establish an interface between the real system and its mathematical representation. Conventional system identification methods generally need differentiable search spaces and they cannot be used for nondifferentiable multimodal search spaces. On the other hand, metaheuristic search algorithms are independent from the search space characteristics and they do not need much knowledge about the real system. The migrating birds optimization algorithm is a recently introduced nature-inspired metaheuristic neighborhood search approach. It simulates the V flight formation of migrating birds, which enables birds …
Classification Of Short-Circuit Faults In High-Voltage Energy Transmission Line Using Energy Of Instantaneous Active Power Components-Based Common Vector Approach, Mehmet Yumurtaci, Gökhan Gökmen, Çağri Kocaman, Semi̇h Ergi̇n, Osman Kiliç
Turkish Journal of Electrical Engineering and Computer Sciences
The majority of power system faults occur in transmission lines. The classification of these faults in power systems is an important issue. In this paper, the real parameters of a 28 km, 154 kV transmission line between Simav and Demirci in Turkey's electricity transmission network is simulated in MATLAB/Simulink. Wavelet packet transform (WPT) is applied to instantaneous voltage signals. Instantaneous active power components are obtained by multiplying instantaneous currents obtained from a voltage source side with these WPT-based voltage signal components. A new feature vector extraction scheme is employed by calculating the energies of instantaneous active power components. Constructed feature …
Some Properties Of Digital H-Spaces,
2016
TÜBİTAK
Some Properties Of Digital H-Spaces, Özgür Ege, İsmet Karaca
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we study certain properties of digital H-spaces. We prove that a digital image that has the same digital homotopy type with any digital H-space is also a digital H-space. We show that the digital fundamental group of a digital H-space is abelian. We give examples that are related to a digital homotopy associative H-space and a $\kappa $-contractible digital H-space. Several important applications of digital H-spaces are given in computer vision and image processing. Finally, we deal with the importance of digital H-space in digital topology and image processing. We conclude that any $\kappa $-contractible digital image …
Performance Evaluation Of A New Efficient H.264 Intraprediction Scheme,
2016
TÜBİTAK
Performance Evaluation Of A New Efficient H.264 Intraprediction Scheme, Sara Hamdy, Mostafa Ibrahim, Mohamed Osman
Turkish Journal of Electrical Engineering and Computer Sciences
The paper presents a new efficient H.264/AVC$ 4 \times 4$ intraprediction scheme. The new prediction scheme is based on the best prediction matrix mode. The main idea behind the new prediction scheme is to combine the most usable intraprediction modes, {vertical - horizontal - DC} , into a new efficient prediction mode. The new prediction scheme is implemented using VHDL and hence it uses the full advantages of inherent parallelism in the hardware. We evaluate the performance of this prediction scheme in terms of compression ratio, peak signal to noise ratio, and bit rate using seven video sequences. Moreover, we …
Identifying Acquisition Devices From Recorded Speech Signals Using Wavelet-Based Features,
2016
TÜBİTAK
Identifying Acquisition Devices From Recorded Speech Signals Using Wavelet-Based Features, Ömer Eski̇dere
Turkish Journal of Electrical Engineering and Computer Sciences
Speech characteristics have played a critical role in media forensics, particularly in the investigation of evidence. This study proposes two wavelet-based feature extraction methods for the identification of acquisition devices from recorded speech. These methods are discrete wavelet-based coefficients (DWBCs) and wavelet packet-based coefficients, which are mainly based on a multiresolution analysis. These features' ability to capture characteristics of acquisition devices is compared to conventional mel frequency cepstral coefficients and subband-based coefficients. In the experiments, 14 different audio acquisition devices were trained and tested using support vector machines. Experimental results showed that DWBCs can effectively be used in source audio …
A Slotted Aloha-Based Cognitive Radio Network Under Capture Effect In Rayleigh Fading Channels,
2016
TÜBİTAK
A Slotted Aloha-Based Cognitive Radio Network Under Capture Effect In Rayleigh Fading Channels, Muhammed Enes Bayrakdar, Sedat Atmaca, Alper Karahan
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a slotted ALOHA-based cognitive radio (CR) network is proposed and the throughput performance of the proposed CR network model under Rayleigh fading channels is examined. Our CR network contains two special groups of users, primary users (PUs) and CR users (CRUs), and they are considered to be sharing a time-slotted-based common communication channel. While PUs can access the channel at any time owing to their legal right, CRUs can only access the channel when it is not occupied by the PUs. In the network model developed, PUs access the channel utilizing time division multiple access as a …
Application Of Kappa Statistics In Sequential Tests For Family-Based Design,
2016
TÜBİTAK
Application Of Kappa Statistics In Sequential Tests For Family-Based Design, Farid Rajabli
Turkish Journal of Electrical Engineering and Computer Sciences
Family-based designs are commonly used in genetic association studies to locate markers associated with diseases. It is a challenging task to collect a large enough sample size, perform a statistical test, and obtain the desired statistical power. The sequential probability ratio test (SPRT) was introduced to overcome the limited sample size problem. However, the drawback of SPRT is that, for the sake of accuracy, the test leaves many markers in a gray zone meaning ``no decision''. In this article, we propose a novel approach: a sequential probability ratio test `plus' (SPRT$+)$ to reduce the number of these gray zone markers. …
